When the harvest failed last year, Niger's government reacted quickly and called on the international community for help.

It knew that without help, a major catastrophe would have no chance of being averted.

"The alarm bell was rung early here. People have lived through 2010 when the response came late. The early warning systems are in place, early indications were there that a slow onset crisis was coming our way," Ms Brown said.

But six months later, the World Food Program is still struggling to raise funds to provide food to all who need it.

It is trying to make do with less than half of the aid that it believes it needs.

"If we don't get all of the resources we need, we are going to have to prioritise," Ms Brown said.

"We'll have to make some difficult decisions about who needs assistance right now to stop them slipping over the edge."

In the Horn of Africa last year there was a rush of donor support when images of starving children began appearing.